Symptoms
When multiple SFTP receive locations are enabled and the number of receive locations is greater than the connection limit set in the SFTP adapter receive location settings, the SFTP adapter may stop receiving locations intermittently.
Note This issue occurs in both Microsoft BizTalk Server 2013 and BizTalk Server 2013 R2.Resolution
Cumulative update information
This issue was first fixed in the following cumulative update of BizTalk Server:
Workaround
If there's no limit on the SFTP server side and the number of SFTP receive locations isn't too great, you can increase the max connection limit in SFTP adapter receive location properties. However, this may bring too much load on the SFTP server.
Status
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
References
For information about the service packs and cumulative update list for BizTalk Server, see KB 2555976: Service pack and cumulative update list for BizTalk Server. For more information about BizTalk Server hotfixes, see KB 2003907: Information about BizTalk hotfixes and cumulative update support.